Card Code

The Card Security Code (CSC), sometimes called Card Verification Value or Code (CVV or CVC), is a security feature for credit card transactions, giving protection against credit card fraud.

MasterCard, Visa and Discover credit and debit cards have a 3 digit code. It is not embossed like the card number, and is always the final group of numbers printed on the back signature panel of the card. New MasterCard and Visa cards feature the code in a separate panel to the right of the signature strip.

American Express cards have a 4 digit code printed on the front side of the card above the number. It is printed flat, not embossed like the card number.

Source: Wikipedia